ABSTRACT
The intestinal triacylglycerol biosynthesis occurs via the monoacylglycerol pathway and the triose-phosphate pathway. The nonruminant animal species primarily make use of the monoacylglycerol pathway, while the ruminant species principally use the triose-phosphate pathway. The 2-monoacylglycerols are reacylated into triacylglycerols by the consecutive action of mono- and diacylglycerol acyltransferases in the villus cell microsomes. Improved methods of handling membrane-bound proteins developed in related areas of research, however, promise a rapid isolation and characterization of the acylglycerol acyltransferases also from the villus cells of the intestinal mucosa. The enzymes involved in the triacylglycerol resynthesis in the intestinal mucosa are usually assayed in vitro using the total tissue homogenate or appropriate subfractions. The phosphatidic acid formed in the intestinal mucosa by the two triose-phosphate pathways remains bound to the endoplasmic reticulum. With the microsomal fraction of guinea pig intestinal mucosa, the highest rate of acyl-CoA synthesis was exhibited for myristic acid.
